In a decision announced late Friday, Judge Lonny Suko ruled that, "for decades Teck's leadership knew its slag and effluent flowed from Trail downstream and are now found in Lake Roosevelt, but nonetheless Teck continued discharging wastes into the Columbia River."
Suko noted an admission from the company that it "had been treating Lake Roosevelt as a 'free,' 'convenient' disposal facility for its wastes."
The decision gives the U.S. Environmental Protection Agency the ability to force Teck to pay for the clean-up, and potentially for any ongoing damages and losses that result from the ongoing contamination. That issue has yet to be determined by the court.
Suko found that from 1930 to 1995, Teck intentionally discharged at least 9.97 million tons of slag that included heavy metals such as lead, mercury, zinc and arsenic.
The judge also found that Teck knew the hazardous waste disposed of in the Columbia River was likely to cause harm.
"We are very pleased with this outcome," John Sirois, chairman of the Colville Business Council, said in a statement. "Now that the Court has found that Teck is liable for its contamination of the Columbia River, we look forward to its participation in cleaning it up and paying for any resulting damages."
The company said Friday that the amount of those costs will be determined in a subsequent phase of the case.
Under a 2006 agreement with the Environmental Protection Agency a remedial study is expected to be completed in 2015. The next phase of the case is not expected to proceed until those studies are complete.
The company said based on their own studies to date, they believe "the compensible value of any damage will not be material."
"(Teck American Inc.) continues to work the with Environmental Protection Agency, the state of Washington, local tribes and others on studies in the Upper Columbia River, which to date have generally shown that the water in the river system meets applicable water quality standards in both Canada and the United States, that the beaches are safe for recreational activities, and that the fish in the river system are as safe or safer to eat than fish in other water bodies in Washington state," Teck said in the statement.
However, they acknowledged that the costs may be "material."
"Until the studies and additional damage assessments are completed it is not possible to estimate the extent and cost, if any, of any remediation or restoration that may be required, or to fully assess (Teck Metals Ltd.'s) potential liability for damages," said the statement.
After eight years of litigation, the company admitted on the eve of a trial last fall that for a century the smelter, operated on the banks of the Columbia in Canada, dumped slag and effluent into the river.
Lead, mercury, arsenic and a myriad of other hazardous materials washed downstream, contaminating the river south of the border.
It's a landmark case that could have implications for mining and other industrial interests on both sides of the border. The Canadian government, the province of British Columbia and the U.S. National Mining Association have all intervened in the case to argue that the issue should be resolved bilaterally.
The case went all the way to the U.S. Supreme Court, which refused to hear Teck's appeal.
Teck argued that the U.S. law that forces companies to clean up contamination sites was never intended to reach across the international border.
About a billion and a half dollars has been spent modernizing Teck's Trail Operations over the past 25 years. A new furnace installed in 1996 cut emissions dramatically.
The company has also spent tens of millions of dollars on environmental rehabilitation, from digging up contaminated gardens and bringing in replacement soil, to replanting dead trees.
The company submitted a remediation plan to Environment Canada in October to deal with leaching of contaminated water from historic